Question

In experiment of heat transfer by convection, water inside the pipe completely gets heated (with the application of heat source). This can be explained best by which of the following statements,

• A. Differences in densities produced between the bottom and the top of water , in turn produce the driving force which continuously circulates the water.
• B. A continuous conductive channel is produced between the different layers of water in the pipe which circulates the heat.
• C. both the above explains correctly
• D. all of the above

Answer 1

The correct option is A Differences in densities produced between the bottom and the top of water , in turn produce the driving force which continuously circulates the water.

When the water in below part of pipe is heated, its density decreases. Hence less density water moves up (shown in red) and cooler water with more density comes down (shown in blue). It is nothing but convection as convection is mode of heat transfer in which heat is transferred in fluid (liquid or gas) by molecular motion.